Reply-To: "Kevin Aylward"
From: "Kevin Aylward"
References: <email@example.com> <7Tbt9.2176$R24.firstname.lastname@example.org> <email@example.com>
Subject: Re: How does a mixer work?
X-Newsreader: Microsoft Outlook Express 6.00.2800.1106
Date: Wed, 23 Oct 2002 07:42:09 +0100
NNTP-Posting-Date: Wed, 23 Oct 2002 07:42:16 BST
"James Meyer" wrote in
> On Tue, 22 Oct 2002 13:53:16 +0100, "Kevin Aylward"
> >Well, this is not really a valid analogy. In the case of the carrier
> >presumption is that it is always the same. With either sidebands the
> >assumption is that they are always changing. If the sidebands were
> >constant, then, by the definition of information they would also
> >no information.
> If we make a deal whereby I will pay you one dollar for every Hz of a
> tone that I will send you via amplitude modulation and if I throw away
> carrier because it is constant in amplitude and therefore contains no
> information and if I throw away both sidebands because they also
> amplitude and therefore contain no information, how will you know how
> I owe you?
Your set-up require *two* states, one with a tone and one without the
tone. Your coding your payment on the tone being on *and/or* off, not
just being on. If you switch the tone on and off so that you can
exchange the knowledge that you are sending, you need some BW or the
tone will take infinite time to turn on.
This is really a bit of a dead issue. This has all been completely
investigated 60+ years ago. Its why there is a science of information
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